Enrichment increases hippocampal neurogenesis independent of blood monocyte-derived microglia presence following high-dose total body irradiation

Marc J. Ruitenberg, Julia Wells, Perry F. Bartlett, Alan R. Harvey, Jana Vukovic

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Birth of new neurons in the hippocampus persists in the brain of adult mammals and critically underpins optimal learning and memory. The process of adult neurogenesis is significantly reduced following brain irradiation and this correlates with impaired cognitive function. In this study, we aimed to compare the long-term effects of two environmental paradigms (i.e. enriched environment and exercise) on adult neurogenesis following high-dose (10 Gy) total body irradiation. When housed in standard (sedentary) conditions, irradiated mice revealed a long-lasting (up to 4 months) deficit in neurogenesis in the granule cell layer of the dentate gyrus, the region that harbors the neurogenic niche. This depressive effect of total body irradiation on adult neurogenesis was partially alleviated by exposure to enriched environment but not voluntary exercise, where mice were single-housed with unlimited access to a running wheel. Exposure to voluntary exercise, but not enriched environment, did lead to significant increases in microglia density in the granule cell layer of the hippocampus; our study shows that these changes result from local microglia proliferation rather than recruitment and infiltration of circulating Cx3cr1+/gfp blood monocytes that subsequently differentiate into microglia-like cells. In summary, latent neural precursor cells remain present in the neurogenic niche of the adult hippocampus up to 8 weeks following high-dose total body irradiation. Environmental enrichment can partially restore the adult neurogenic process in this part of the brain following high-dose irradiation, and this was found to be independent of blood monocyte-derived microglia presence.

Original languageEnglish
Pages (from-to)150-159
Number of pages10
JournalBrain Research Bulletin
Volume132
DOIs
Publication statusPublished - 1 Jun 2017

Fingerprint Dive into the research topics of 'Enrichment increases hippocampal neurogenesis independent of blood monocyte-derived microglia presence following high-dose total body irradiation'. Together they form a unique fingerprint.

Cite this